Through this research career development award, I will complete the initial steps to establish myself as an independent researcher in HIV/AIDS behavioral research to reduce health disparities in Latino communities infected with HIV. Using didactic and mentored learning, I will improve upon my existing behavioral, qualitative, and quantitative research skills to address the issue of low participation in HIV/AIDS clinical trials in Latino communities. Proportionate representation of minority populations in research trials is necessary to improve research capacity to generalize results to diverse populations infected with HIV. My specific research aims are to: 1) Describe and understand the attitudes, beliefs, cultural and social norms, provider and system influences relating to entry into clinical trials in HIV+ Mexican-origin Latinos, and 2) Develop and pilot test an intervention for improving understanding and acceptance of HIV clinical trials participation by HIV+ Mexican-origin Latinos and their communities. The theoretical framework of the research plan is the Behavioral Model of Health Services Use (Andersen, Aday, et al.). The research plan will be carried out in three phases, each phase linked to a career development objective and activity. In Phase 1 I will conduct formative research using qualitative methods with HIV+ Mexican-origin Latinos, including design and implementation of an in-depth interview protocol and focus group questions to explore factors to consider in attempting to improve clinical trials participation in Latino populations. In Phase 2 I will carry out qualitative analysis, develop a social cognitive model of participation in research, develop research hypotheses, and develop and pilot test a survey to test the social cognitive model in HIV+ Mexican-origin Latinos. In Phase 3 I will validate the survey, analyze and report outcomes, design and pilot-test a behavioral intervention to increase clinical trials participation in HIV+ Mexican-origin Latinos, and finally, use intervention pilot data to prepare an R01 proposal to the NIH to promote participation of HIV+ Latinos in clinical trials.